My wife rang me at work one day to complain that our brand new $1000 lawn mower was smoking and running rough. I had no idea so told her to turn it off and I will check when I got home. Investigation at home (show me which can you filled the mower from dear) revealed she had been running our petrol lawn mower on diesel for about 1/2 an hour. Didn't seem to hurt it. Cleaned it out, put some petrol in and away it went. The dealer gave me some technical explanation about how a small 4 stroke petrol engine can actually run (poorly) on diesel but my eyes glazed over. Still hunting for a 65hp cab tractor to make hay